Dibutyltin Compounds Research Articles

Organotin(IV) complexes derived from 2,6-diacetylpyridine bis(2-hydroxybenzoylhydrazone) as prospective anti-proliferative agents: Synthesis, characterization, structures and in vitro anticancer activity

Six organotin(IV) complexes, viz., [Me2Sn(L)] (1), [n-Bu2Sn(L)] (2), [n-Oct2Sn(L)] (3), [Bz2Sn(L)]·0.5C7H8 (4), [n-BuSn(L)Cl] (5), and [PhSn(L)Cl] (6), were synthesized using a 2,6-diacetylpyridine bis(2-hydroxybenzoylhydrazone), H2L. Compounds were characterized by Fourier transform infrared (FT-IR), High-resolution mass spectrometry (HRMS), and solutions Fourier transform nuclear magnetic resonance (FT-NMR) spectroscopies. The structures 1–6 were established by single-crystal X-ray diffraction (SC-XRD) analysis. Diffraction results evidenced that complexes 1–6 were seven-coordinated mononuclear species with the equatorial plane comprising the pentagonal N3O2 chelate ring of the doubly deprotonated L and two axial ligands, either R (R = Me, n-Bu, n-Oct, Bz) or R (n-Bu or Ph) and Cl ligands. Additionally, the photophysical properties were examined due to the enhanced conjugation and rigidity of the molecules while thermogravimetric analysis was carried out to evaluate the thermal stabilities of compounds. The anti-proliferative activity of the complexes 1–6 was tested against prostate cancer cells (DU-145) and normal human embryonic kidney cells (HEK-293). Among the compounds, dibutyltin compound 2 exhibited increased anti-proliferative activity, with an IC50 value of 6.16 ± 1.56 μM. The investigation of its mechanism of action involves using AO/EB (acridine orange/ethidium bromide) and ROS (reactive oxygen species) generation assays. This likely detects apoptotic morphological alterations in the nucleus of the cells, with ROS generation ultimately leading to apoptosis and cell death. The superior activity of 2 may be attributed to the C···H contacts and respective higher de outside and di inside distances from the Hirshfeld surface. Thus, these compounds could be a promising alternative to classical chemotherapy agents.

Validation of the testing method for the determination of dibutyltin compounds in food utensils, containers, and packaging products made from polyvinyl chloride using gas chromatograph-mass spectrometry with nitrogen as a carrier gas

Validation of the testing method for the determination of dibutyltin compounds in food utensils, containers, and packaging products made from polyvinyl chloride using gas chromatograph-mass spectrometry with nitrogen as a carrier gas

Reactive blending and transesterification-induced degradation of isosorbide-based polycarbonate blends

We report the reaction of bio-renewable isosorbide-based polycarbonate (IcC-PC) with poly(bisphenol A carbonate) (BPA-PC) by melt-blending in the presence of dibutyltin dilaurate (DBTDL). The blends formed copolymers and transformed into transparent alloys with a single Tg after melt-blending. A remarkable reduction in molecular weight was observed in the reactively blended products. 1H NMR and 13C NMR results showed that the carbonate group of IcC-PC is less vulnerable to nucleophilic attack than that of BPA-PC and that transesterification is initiated by the exchange reaction between the laurate ligands of DBTDL and the carbonate groups of BPA-PC. Tin-containing BPA-PC chains were proposed to react with the carbonate group of IcC-PC via a coordination-insertion mechanism to produce the (IcC-PC)-(BPA-PC) copolymer. The hydroxyl end-groups of IcC-PC were also involved in transesterification under the catalysis of dibutyltin compounds and converted into low-reactive phenolic end-groups of BPA-PC. Degradation in the IcC-PC/BPA-PC blends after adding DBTDL was mainly caused by the exchange reaction between DBTDL and BPA-PC, hydrolysis, and phenolysis of IcC-PC and BPA-PC under the catalysis of dibutyltin compounds. Among these reactions, hydrolysis played the major role and occurred mostly at the BPA-PC chains.

Dibutyltin Compounds Effects on PPARγ/RXRα Activity, Adipogenesis, and Inflammation in Mammalians Cells.

Organotins are a group of chemical compounds that have a tin atom covalently bound to one or more organic groups. The best-studied organotin is tributyltin chloride, which is an environmental pollutant and an endocrine disruptor. Tributyltin chloride has been shown to bind to PPARγ/RXRα and induces adipogenesis in different mammalian cells. However, there are few studies with other organotin compounds, such as dibutyltins. The aim of this study was to investigate the effect of dibutyltins diacetate, dichloride, dilaurate, and maleate on the transcriptional activity of the nuclear PPARγ and RXRα receptors, and on adipogenesis and inflammation. Analogous to tributyltin chloride, in reporter gene assay using HeLa cells, we observed that dibutyltins diacetate, dichloride, dilaurate, and maleate are partial agonists of PPARγ. Unlike tributyltin chloride, which is a full agonist of RXRα, dibutyltins dichloride and dilaurate are partial RXRα agonists. Additionally, the introduction of the C285S mutation, which disrupts tributyltin chloride binding to PPARγ, abrogated the dibutyltin agonistic activity. In 3T3-L1 preadipocytes, all dibutyltin induced adipogenesis, although the effect was less pronounced than that of rosiglitazone and tributyltin chloride. This adipogenic effect was confirmed by the expression of adipogenic markers Fabp4, Adipoq, and Glut4. Exposure of 3T3-L1 cells with dibutyltin in the presence of T0070907, a specific PPARγ antagonist, reduced fat accumulation, suggesting that adipogenic effect occurs through PPARγ. Furthermore, dibutyltins dichloride, dilaurate, and maleate inhibited the expression of proinflammatory genes in 3T3-L1 cells, such as Vcam1, Dcn, Fn1, S100a8, and Lgals9. Additionally, in RAW 264.7 macrophages, tributyltin chloride and dibutyltin dilaurate reduced LPS-stimulated TNFα expression. Our findings indicate that dibutyltins diacetate, dichloride, dilaurate, and maleate are PPARγ partial agonists and that dibutyltins dichloride and dilaurate are also partial RXRα agonists. Furthermore, dibutyltins induce adipogenesis in a PPARγ-dependent manner and repress inflammatory genes in 3T3-L1 and RAW 264.7 cells. Although dibutyltins display some partial PPARγ/RXRα agonistic effects, the translation of cell-based results assays into in vivo effects on inflammation and insulin resistance is not entirely known. Nevertheless, further studies are necessary to address their effects in different periods of life and to elucidate the actions of organostanic compounds in whole-body context.

New dibutyltin(IV) ladders: Syntheses, structures and, optimization and evaluation of cytotoxic potential employing A375 (melanoma) and HCT116 (colon carcinoma) cell lines in vitro

Synthesis and spectroscopic properties of seven new dibutyltin(IV) compounds of 2-{(E)-4-hydroxy-3-[(E)-4-(aryl)iminomethyl]phenyldiazenyl}benzoic acids (LnHH′; n=2–8) with general formula {[Bu2Sn(LnH)]2O}2 (1–7) are reported. The compounds were characterized by elemental analysis and by UV–Visible, fluorescence, IR, 1H, 13C and 119Sn NMR spectroscopies. Solid state structures of dibutyltin(IV) compounds 1–3, 6 and 7 were accomplished from single crystal X-ray crystallography which reveal the common ladder-type structure with two endo- and two exo-Sn atoms. The redox properties of LnHH′ (n=2–4, 7 and 8) and their diorganotin(IV) compounds 1–3, 6 and 7 were also investigated by cyclic voltammetry. In general, the dibutyltin(IV) derivatives exhibited significant in vitro cytotoxic potency towards A375 (melanoma) and HCT116 (colon carcinoma) cell lines as determined by several experiments, like Live and Dead assay, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cell viability assay, LDH (lactate dehydrogenase), cleavage of caspases and PARP (poly(ADP-ribose)polymerase), and DNA fragmentation. Dibutyltin(IV) compounds increase cell death without cytolysis and decreases membrane fluidity, without interfering with p53. Among the dibutyltin(IV) compounds, compound 6 was found to be the most potent, with an IC50 value of 78nM. A mechanism of action for tumor cell death is proposed.

BUTYLTIN RESIDUES IN SEDIMENTS FROM THE EASTERN GULF OF THAILAND

Concentrations of monobutyltin (MBT), dibutyltin (DBT) and tributyltin (TBT) compounds were analyzed in surface sediment samples collected from twelve stations along the Eastern Gulf of Thailand. The total butyltin (∑BTs) concentrations ranged between <1 and 109.7 ng g (dry weight). The overall concentration ranges found in the sediments were from <1 to 79.81 ng g-1 for MBT, from <1 to 9.5 ng g -1 for DBT, and from <1 to 29.8 ng g-1 for TBT, on a dry weight basis. MBT generally prevailed in most of the samples, suggesting the occurrence of old inputs of butyltin compounds in the area. Butyltin compounds were also measured in Nassarius sp., where ∑BTs concentrations were found to range between <1 and 238 ng g-1 (wet weight). The level of butyltin compounds in gastropod tissue samples tended to be related to that of the sediments and percentage of imposex incidence.

Synthesis and Potency Study of Some Dibutyltin(IV) Dinitrobenzoate Compounds as Corrosion Inhibitor for Mild Steel HRP in DMSO-HCl Solution

Following our succes in the synthesis ofsome derivative of organotin(IV) carboxylates, in this work we reported the corrosion inhibitor study of three dibutyltin(IV) compound using ligan 0f 2-, 3- ang 4-nitrobenzoic acid. All the three synthesized compounds were characterized by spectroscopy techniques also based on the microanalytical and physical data. The corrosion inhibition was evaluatedwith potentiodynamic polarization technique using ER644 Integrated Potentiostat eDAQ type on mild steel hot rolled plate (HRP) in DMSO-HCl solution. The results indicated that the these compounds showed interesting inhibition activity with percentage of inhibition efficiency (% IE) of 59.3, 60.5, and 61.2 % for dibutyltin(IV) 2-nitrobenzoate, 3-nitrobenzoate and 4-nitrobenzoate, respectively. These three dibutyltin(IV) compounds have been shown promising to be potentially used as anticorrosion inhibitors.

The Effectiveness of Dibutyltin (IV) and Di-tert-butyltin (IV) Alkyl-phenyl Dithiocarbamate Compounds as Larvicide against <em>Aedes aegypti</em> Linn. (Diptera: Culicidae) in Laboratory

Extensive use of insecticides to control dengue vectors has led to the development of mosquito resistance, environmental pollution and undesirable effects on non target organisms. Thus, the potential of organotin (IV) compounds has been explored to be developed as insecticides to obviate the existing problems. The aim of this study was to examine the larvicidal effect of dibutylt in (IV) and di-tert-butyltin (IV) alkyl-phenyl dithiocarbamate compounds against Aedes aegypti Linn. in laboratory. Larvicidal bioassay test of four compounds dibutyltin (IV) ethyl phenyl dithiocarbamate, di-tert-butyltin (IV) ethyl phenyl dithiocarbamate, dibutyltin (IV) butyl phenyl dithiocarbamate and di-tert-butyltin (IV) butyl phenyl dithiocarbamate against third instar larvae of A. aegypti was carried out. The study indicated that dibutyltin (IV) butyl phenyl dithiocarbamate showed the highest larvicidal effect with LC50 and LC90 values of 0.59 and 3.91 ppm, respectively. However, the other three compounds showed lower larvicidal effects. Dibutyltin (IV) ethyl phenyl dithiocarbamate showed moderate larvicidal effect with LC 50 and LC90 values of 4.45 and 11.08 ppm, respectively, followed by di-tert-butyltin (IV) butyl phenyl dithiocarbamate compound with LC50 and LC90 values of 5.08 and 11.50 ppm, respectively. Di-tert-butyltin (IV) ethyl phenyl dithiocarbamate compound showed the least larvicidal effect with LC 50 and LC90 values of 8.59 and 36.74 ppm, respectively. Morphological anomalies such as elongated neck region, shortened length and destructed digestive tract in the larvae were observed and recorded during the larvicidal bioassay testing. As a conclusion, dibutyltin (IV) butyl phenyl dithiocarbamate compound is the most effective compound against the dengue vector, A. aegypti and has the potential to be explored as a larvicide. Further study is needed to ensure that this compound can be used safely as a larvicide.

Syntheses, characterization, X-ray diffraction studies and in vitro antitumor activities of diorganotin(IV) derivatives of bis(p-substituted-N-methylbenzylaminedithiocarbamates)

Six new organotin(IV) dithiocarbamate complexes of the type R2SnL2, where (L=p-bromo-N-methylbenzylaminedithiocarbamate and p-fluoro-N-methylbenzylaminedithiocarbamate, and R=dimethyl-, dibutyl- and diphenyl-) have been synthesized in good yields. The isolated ligands and their respective diorganotin complexes were suitably characterized by elemental analysis, FT-IR, 1H, 13C and 119Sn NMR spectroscopies. The crystal structures of three diorganotin(IV) complexes have been determined by X-ray crystallography. The spectroscopic and single crystal X-ray diffraction data illustrate that the dithiocarbamato ligands in the dimethyltin(IV) and diphenyltin(IV) derivatives 1, 2 and 6 are monodentate and the geometry at tin is best described as a distorted tetrahedron. The dimethyltin(IV) and dibutyltin(IV) compounds were evaluated for their in vitro antiproliferative activities. The dibutyltin(IV) complexes showed moderate cytotoxicities toward human leukemic lymphoblastoma Jurkat cells, lymphoblastoma K-562 cells, hepatoblastoma HepG2 cells and mouse fibroblast L929 cells.

Aeromonas molluscorum Av27 is a potential tributyltin (TBT) bioremediator: phenotypic and genotypic characterization indicates its safe application

Aeromonas molluscorum Av27 is an estuarine bacterium highly resistant to tributyltin (TBT). Also, the strain is able to degrade TBT into the less toxic compounds dibutyltin and monobutyltin. Therefore, this bacterium has potential to be employed in bioremediation processes. In this context, defining its biological safety is crucial. With that purpose a number of intrinsic characteristics, usually present/associated with virulent strains, were investigated. Few virulence factors were detected in strain Av27. For instance, a DNase gene is present, but it is not apparently expressed in vitro. Motility, adherence factor and phospholipase activity were also detected. Additionally, cytotoxicity to Vero cells was negative. Resistance to penicillin (10μgml(-1)), amoxicillin/clavulanic acid (30μgml(-1)) and cephalothin (30μgml(-1)) and also to the vibriostatic agent O/129 was observed. Five plasmids (4, 7, 10, 100kb and one greater than 100kb) were identified. No Class I and II integrons were detected. Study of the optimal growth conditions showed that Av27 easily adapts to different environmental conditions. Overall, the results suggest that A. molluscorum Av27 can be considered safe to use to bioremediate TBT in contaminated environments.

Thermal analysis of new dimethyl/dibutyl tin(IV) compounds with amino acids

Six diorganotin(IV) compounds with amino acids of general formula [(CH3)2SnAACl]2 and [(CH3CH2CH2CH2)2SnAACl]2 (where AA = l-methioninate, l-cysteinate, and l-tryptophanate) were synthesized by reacting dimethyltin(IV) dichloride (M) and dibutyltin(IV) dichloride (B) with l-methionine (M1) or l-cysteine (C) or l-tryptophan (T) using acetonitrile as solvent and designated as MM1, MC, MT, BM1, BC, and BT. The structural characterization of dimethyltin(IV) and dibutyltin(IV) compounds were done using elemental analysis, FT-IR, 1H-NMR, 13C-NMR, and 119Sn-NMR spectroscopy. The thermal properties of the synthesized compounds were studied by thermogravimetric analysis and differential scanning calorimetry techniques in a dynamic atmosphere of nitrogen. The thermal decomposition mechanisms were similar for compounds MM1, BM1, MC, BC, and occurred in one step, while in compounds MT and BT it occurred in two consecutive steps. The TG curves of the MT and BT compounds suggest the loss of the ligand (AA) in the first step, with probable formation of a tin oxide R2SnO intermediate. At the end of the second step free tin is obtained similar to the MM1, BM1, MC, BC in accordance with the stoichiometry of the related compounds.

Synthesis, characterization, crystal structures and electrochemical studies of organotin(IV) carboxylates

Four new organotin(IV) compounds [Me3SnL] (1), {[Me2SnL]2O}2 (2), Bu2SnL2 (3) and [Bu3SnL] (4), where L = O2C(C2H5)CCHC6H4F have been synthesized by refluxing the corresponding organotin(IV) chlorides with sodium (E)-2-(2-fluorobenzylidene) butanoate (NaL) in dry toluene except 2 for which Me2SnO was refluxed with (E)-2-(2-fluorobenzylidene) butanoic acid (LH) in the same solvent. NaL and all the compounds were characterized by FT-IR, 1H NMR and 13C NMR spectroscopy. NaL and compounds 1 and 2 were also characterized by X-ray single crystal analysis which confirmed a linear polymeric structure for compound 1 and a stannoxane for 2. The structural analyses have shown a bridging behavior of the ligand in trimethyl- and tributyl-, chelating as well as bridging behavior in dimethyl- and a chelating bidentate mode of coordination in dibutyltin(IV) compound which is also confirmed from the crystal analysis for compounds 1 and 2. Cyclic voltammetry was used to evaluate the electrochemical, kinetic and thermodynamic parameters for the electron transfer processes of compounds 1–4. Predominantly adsorption controlled redox processes were exhibited by the slope of log ipvs. −log v plots. The values of the diffusion coefficient (Do) indicated the role of solvent in the mobility of the electro-active species to some extent but the overall rate of the redox process was typical of the adsorption controlled process and could not be explained on the basis of solvation effects. The values of formal potential and charge transfer coefficient were also calculated.

Regulation of gene expression in mouse germ cells upon exposure to tetrabutyltin

Tetrabutyltin is the starting material of the tributyltin and dibutyltin compounds. These tin compounds are starting materials for a wide range of organotin compounds used as stabilizers for PVC, biocides, fungicides, and anti-biofouling agents. It is commonly known that some of the environmental chemicals affect the human endocrine system. Since the 1970s, the harmful effects of endocrine disrupting chemical (EDC), Tetrabutyltin (TTBT) have been extensively studied. In the present study, we analyzed the effect of TTBT on gene regulation and expression of genes in mouse germ cells. Mouse germ cells were treated with TTBT for 3 and 24 hrs, and global gene expression was analyzed by using customized Agilent mouse arrays. We identified genes that were >2-fold differentially expressed in TTBT-treated cells than control cells (P<0.05) and analyzed their functions through Gene Ontology analysis. In a total number of 687 genes, there was differential expression between TTBT-treated and control cells. About 471 and 350 genes exhibited 2-fold (P<0.05) increased or decreased expression at 3 and 24 hrs, respectively. Additionally, in 134 genes, common and significant changes were observed in two-time series. Functional analysis of these genes showed that there were significant enrichments in some of the processes related to the reproduction such as, female gamete generation, homeostatic process, cell differentiation, response to chemical stress and reproductive process. In conclusion, the present study provides an insight on the effects of TTBT on mouse germ cells. Furthermore, it also increases our knowledge on the underlying molecular mechanisms on the adverse effects of organotin on the reproductive system.

Adsorption and desorption of tetraalkyllead and dibutyltin compounds on contaminated soils

Adsorption and desorption of di-n-butyltin (IV) (DBT), tetramethyllead (TML), and tetraethyllead (TEL) on four types of soil were studied. Although, all K d values for desorption are higher than the K d values for adsorptions, which shows that the adsorption process is reversible, the lower percentages of desorption indicate that very low concentration of these organometallic compounds can be more easily leached from the soil. The adsorption ranging between 48.8% and 88.3% for DBT, between 9.1% and 38.3% for TEL, and between 24.9% and 44.2% for TML was measured. The desorption was obtained between 9.4% and 23.7% for DBT, between 19.3% and 38.9% for TEL, and between 21.5% and 32.7% for TML. These results show that the nonpolar (TML, TEL) organometallic compounds can be easier leached than the ionic forms (DBT). Adsorption kinetics and adsorption as a function of pH were also evaluated. DBT and tetraalkyllead adsorption equilibrium were reached after 12 and 24 h, respectively. The tetraalkyllead is strongly adsorbed at pH 7–8 and DBT at pH 6.

Effects of various pesticides on human 5α-reductase activity in prostate and LNCaP cells

Certain pesticides are able to disturb the sex steroid hormone system and to act as antiandrogens. While the different underlying mechanisms remain unclear, inhibition of 5α-reductase, the enzyme which is indispensable for the synthesis of DHT and thus normal masculinization, appears to be one of the sensitive targets for endocrine disruption. We therefore tested several endocrine disrupters with antiandrogenic effects in vivo for their influence on 5α-reductase activity in two different test systems: (a) an enzyme assay with human Lymph Node Carcinoma of Prostate (LNCaP) cells and (b) an enzyme assay with human prostate tissue homogenate. The selected pesticides and industrial compounds were monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), triphenyltin (TPT), diuron, fenarimol, linuron, p, p′DDE, prochloraz and vinclozolin. The synthetic androgen methyltestosterone and the synthetic antiandrogen flutamide, as well as the 5α-reductase inhibitor finasteride served as control compounds. The effect of the organotin compounds DBT, TBT and TPT on enzyme activity was approximately the same in both test systems, with IC 50 values ranging between 2.7 and 11.2 μM, while in prostate tissue, methyltestosterone and prochloraz proved to be stronger inhibitors (IC 50 values of 1.9 and 12.4 μM) than in LNCaP cells (IC 50 values of 13.2 and 53.2 μM). The inhibitory impact of finasteride was approximately 130 times stronger in prostate tissue than in LNCaP cells. Fenarimol, flutamide, linuron and p, p′DDE inhibited 5α-reductase activity only at very high concentrations (IC 50 ⩾ 24 μM) in prostate homogenates, and not at all in LNCaP cells. On average, the IC 20 values were 3.5 times lower than the IC 50 values. Diuron, MBT and vinclozolin exerted no effect in either of the test systems. The finding of pesticides acting as 5α-reductase inhibitors might be of clinical relevance. As a screening tool for putative ED, the tissue assay is the more practical and sensitive method. However, the cell assay can, to some extent, reflect particular cell processes since the living cell is able to compensate moderate toxicological effects of the ED on cell viability, and possibly also their impact on 5α-reductase activity.

Contamination of natural and cultured mussels (Mytilus galloprovincialis) from the northern Adriatic Sea by tributyltin and dibutyltin compounds

AbstractThe levels of tributyltin (TBT) and dibutyltin (DBT) compounds were measured by gas chromatography ion‐trap mass spectrometry (GC–MS/MS) in natural and cultured mussels (Mytilus galloprovincialis) from the northern Adriatic Sea in spring 2003. The highest (725 ng g−1 dry weight) and lowest levels (198 ng g−1 dry weight) of butyltins (TBT + DBT) were found in native mussels from the Lagoon of Venice, with the higher values being detected in specimens collected next to a dockyard and the lower values in specimens from a location characterized by strong water exchanges between the lagoon and the Adriatic Sea. The two cultured samples exhibited intermediate concentrations, with marine harvested samples being more contaminated than those from the lagoon.Concentrations of TBT were higher than those of DBT for several reasons: the limited capability of bivalves to metabolize TBT and their ability to accumulate it (with recent input of TBT into the environment as TBT‐based anti‐fouling paints being the most important contributor of organotin contamination in our study area); and higher lipophilicity of TBT than DBT. In order to find correlations between organotin pollution and the state of nourishment of the mussels, the condition index was also evaluated as the mass ratio of meat dry weight to shell dry weight. There was no correlation between condition index and butyltin concentrations. These results indicate that condition index could not give information about stress conditions, as the contamination level is probably too low to cause significant reductions in mussel growth. Copyright © 2004 John Wiley &amp; Sons, Ltd.

Search for the contamination source of butyltin compounds in wine: agglomerated cork stoppers.

A possible butyltin contamination source in wine was studied in this paper. Agglomerated cork stoppers, which were produced in Portugal, Spain, and Italy, used in wine bottles were examined. The domestic cork products, cork granules, and mucus used for cork products were also analyzed. The levels of mono- and dibutyltin compounds in corks were found in the range from <0.0024 to 3.3 and from <0.0029 to 6.7 microg of Sn/g, respectively. A low level of tributyltin contamination was also found in 2 of 31 tested samples. The presence of butyltin compounds in agglomerated cork stoppers was confirmed by GC-MS. Experimental results indicated that all overseas agglomerated cork stoppers studied contained mono- and/or dibutyltins. Butyltins were not detected in cork granules, mucus, most of the natural cork stoppers, and domestic agglomerated cork products. The concentrations of mono- and dibutyltins increased with the time in a 30-day experiment, showing that butyltin compounds can leach from agglomerated cork to the wine. When the butyltin concentrations in wine samples were compared with their levels in the corresponding agglomerated cork stoppers, a correlation was found. The potential harm of such food contamination was evaluated by the toxic research of butyltin compounds using Daphnia sp. as the experimental model.

SPME-GCMS for speciation of butyltin compounds in marine environment

A method for determination of butyltin species using SPME-GCMS in environmental samples has been standardised. The ionic butyltin compounds present in seawater and sediment samples were converted to their hydride forms using sodium tetrahydroborate (NaBH 4 ). These derivatized compounds were extracted using headspace solid phase microextraction (SPME) technique. A polydimethylsiloxane (PDMS) coated fibre (100 μm film thickness) was used to extract butyltin hydrides. The extracted analytes were then transferred to a GC-MS system for desorption, separation and quantification. The detection limits obtained with SPME-GCMS for monobutyl, dibutyl and tributyl tin compounds for different matrices varied between 0.1 and 0.5 picogram. The optimized method was applied for the speciation study of butyltin compounds in seawater and sediment from different part of the Thane Creek. The levels of butyl tin compounds in sediments of Thane Creek varied from 32-178 ng/g while in Creek water it varied from 2-35 ng/l.

Determination of organotin compounds in polyvinyl chloride toys

Organotin compounds in polyvinyl chloride toys were determined by GC/MS after ethyl derivatization with sodium tetraethylborate. The samples were 12 balls, 12 soft toys, 10 food toys and 13 face masks for children. Monooctyltin, dioctyltin and trioctyltin compounds were found in all face masks at the levels of 74.8-917 micrograms/g. 474-3,960 micrograms/g and 1.0-213 micrograms/g, respectively. They also were detected in 6 balls, 4 soft toys and 1 food toy. Monomethyltin and dimethyltin compounds were found in 8 face masks at the levels of 40.9-227 micrograms/g and 222-1,450 micrograms/g, respectively. Monobutyltin and dibutyltin (DBT) compounds were found in 1 ball, 3 food toys and 5 face masks. In particular, 1 ball and 4 face masks contained toxic DBT at the levels of 527-999 micrograms/g.

Determination of organotin compounds in plastic products by GC/MS after ethyl derivatization with sodium tetraethylborate

A simultaneous determination method for 9 organotin compounds in polyvinyl chloride (PVC) and silicone products used as kitchen utensils and food packages was developed using ethyl derivatization with sodium tetraethylborate (NaBEt4). Organotin compounds were extracted with acetone-hexane (3:7) from the samples after acidification and the extract was filtered and concentrated at under 40 degrees C. After centrifugal separation, these compounds were derivatized with 2% NaBEt4 solution and determined by GC/MS. This method was applicable for simple routine analysis. Recoveries of spiked compounds were 49.1-118.1% for 3 PVC products and 88.8-102.2% for a siliconized paper. Monooctyltin, dioctyltin and trioctyltin compounds were found in all PVC food containers at the levels of 123-1,380 micrograms/g, 1,770-13,200 micrograms/g and 6.6-139 micrograms/g, respectively. They also were found in 3 gloves, 5 spouts, 1 hose and 5 pipes. Some PVC products contained monomethyltin, dimethyltin, trimethyltin, monobutyltin and dibutyltin compounds at the levels of 97.3-433 micrograms/g, 96.5-5,120 micrograms/g, 8.5-24.9 micrograms/g, 1.2-852 micrograms/g and 1.2-29.4 micrograms/g, respectively.